Negative resistance element circuit combinations

Abstract

Occurrence of high field domain in the conventional Gunn diode is prevented by covering a solid body such as a semiconductor element partially or wholly by a dielectric member or by a control element such as a metallic layer coupled reactively with the solid body through a dielectric member, whereby a solid state element having a negative differential conductivity is obtained. Such a type of negative-resistance solid state element, together with its various modes of embodimental construction disclosed herein, affords a superior solid state element which is applicable to amplifiers, oscillators, and the like of millimeter or submillimeter bands.

What I claim is: 
     
       1. An amplifier line comprising, in combination: at least one metal conductor forming a transmission line; and a solid state element disposed inside said metal conductor, said solid state element comprising a semiconductor element exhibiting a negative differential conduction in a high electric field, a dielectric layer covering said semiconductor element, and ohmic electrodes attached in spaced apart relationship to said semiconductor element. 
     
     
       2. An amplifier device comprising: a plurality of a solid state elements arranged in series along the propagation direction of an electric wave; each of said elements comprising a semiconductor body having two ends and exhibiting a negative differenetial conduction in a high electric field, a dielectric layer covering said semiconductor body, and electrodes attached respectively to said ends of said semiconductor element; a d.c. voltage source; and means connecting the electrodes of all said solid state elements in parallel to said d.c. voltage source. 
     
     
       3. In a signal translating device, a semiconductor body which exhibits a region of negative differential mobility in its drift-velocity electric field characteristic in response to a biasing electric field between first and second spaced apart electrical contacts on said body, means for injecting an AC signal into said semiconductor body at the negative end of said field, means for extracting an AC signal from said semiconductor body at the positive end of said field, and means for inhibiting oscillation in said device between said signal injecting means and said signal extracting means, whereby said AC signal injected is amplified between said signal injecting means and said signal extracting means, said means for inhibiting oscillation comprising a metal layer disposed between said means for injecting an A.C. signal into said semiconductor body at the negative end of said field and said means for extracting an A.C. signal from said semiconductor body at the positive end of said field, but not in ohmic contact with said body, and means connecting said metal layer to circuit ground for shunting RF fields to ground, thereby lowering gain per unit length of said body between said injecting means and said extracting means. 
     
     
       4. In a signal translating device, a semiconductor body which exhibits a region of negative differential mobility in its drift-velocity electric field characteristic in response to a biasing electric field between first and second spaced apart electrical contacts on said body, means for injecting an AC signal into said semiconductor body at the negative end of said field, means for extracting an AC signal from said semiconductor body at the positive end of said field, and means for inhibiting oscillation in said device between said signal injecting means and said signal extracting means, whereby said AC signal injected is amplified between said signal injecting means and said signal extracting means, said means for inhibiting oscillation comprising a metal layer disposed between said means for injecting an A.C. signal into said semiconductor body at the negative end of said field and said means for extracting an A.C. signal from said semiconductor body at the positive end of said field, but not in ohmic contact with said body, thereby lowering gain per unit length of said body between said injecting means and said extracting means. 
     
     
       5. An amplifier device comprising, in combination: a solid body composed of semiconductor material having at least two ends and exhibiting a negative differential conductivity characteristic when placed in a high electric field; an electrode ohmicly attached to each of said ends; means for applying a bias voltage across said electrodes to produce a high electric field to cause said solid body to exhibit a negative differential conductivity; a dielectric member covering at least one part of said body and being effective to suppress high field domains in said body; means for supplying an input signal to be amplified to said solid body at the negative side thereof; and means for extracting an output signal comprising an amplified version of said input signal from said solid body at the positive side thereof.